The present invention relates generally to devices that illuminate fluid level verification gauges which are operable to measure the amount of fluid present in a fluid container such as a tank, machine, or other article of manufacture and more specifically, devices where the source of illumination is integrated with the fluid level gauge as a single unit and activated by a sensor that detects movement such as the presence of a person. Alternatively, the present invention relates generally to devices that illuminate fluid reservoirs which are operative to dispense fluids, such as lubricants to a machine or article of manufacture. Again, more specifically devices where the source of illumination is integrated with the fluid reservoir as a single unit and activated by a sensor that detects movement such as the presence of a person.
Fluid level verification devices are known in the art. A fluid level verification device provides for an inspection tube having an interior conduit dimensioned to create an interference fit with an o-ring used to hermetically seal the inspection tube to one or more end members. A more common fluid level verification device in the art provides for an inspection tube whereby both ends incorporate grooving and o-rings that seal with opposing end members to isolate the inspection tube from the environment. A fluid level verification device in the art may also provide for an external shield positioned about the inspection tube to protect it from damage.
Illuminating a fluid level verification apparatus is also known in the art. For example, the prior art describes a lighting assembly that aids in the visual indication of the fluid level in a container by utilizing fiber optic light cables in combination with a gas filled light source to illuminate the transparent fluid level indication viewing window. Another fluid level verification apparatus in the prior art provides for a separate backlighting illumination apparatus that attaches to sight glasses that indicate fluid level or flow. Yet another fluid level verification apparatus in the prior art provides a liquid level gauge having a chamber connected to a tank containing a liquid, a transparent member in the wall of the chamber, a light transmitting transparent rod extending through the chamber, and a light source shining rays of light into the rod from the exterior.
In addition, at present there are a variety of reservoirs for containing and dispensing fluids, such as lubricants. One common prior art reservoir uses a cylindrical or rectangular container with a screw on top cover. Another uses a cylindrical or rectangular container with a screw on bottom cover. In both instances, the containers may be made from glass or plastic. Another typical prior art reservoir utilizes a top end plate, a bottom end plate, a cylindrical body and a centrally located tie rod to secure the end plates to each end of the cylindrical body. It is critical that these reservoirs have sufficient levels of liquid, such as a lubricant within the reservoir and that these reservoirs are refilled before reaching an empty condition.
Prior art has successfully introduced the ability to verify the fluid level in fluid level gauges and reservoirs in dark or dimly lit environments through various illumination devices. However, although some of the prior art contemplates sources of illumination that are integral to the fluid level gauge, no integral sources of illumination are coupled with a sensor that actives the source of illumination by the detection of motion or another non-contact means. The current sources of illumination embodied in the prior art require either indefinite activation of a light source or activation through a manual switching mechanism. Therefore, a need exists for a fluid level verification apparatus with an integral source of illumination coupled with an activating sensor that detects the presence of a foreign body or movement.